Method for producing glycidol

Abstract

Disclosed is a method for producing glycidol by decarboxylation of glycerol carbonate. In the method, an ionic liquid catalyst is added for the reaction. According to the method glycidol can be produced in high yield and selectivity. The method enables the production of glycidol in an easy, simple and environmentally friendly way.

What is claimed is: 
     
       1. A method for producing glycidol by decarboxylation of glycerol carbonate, wherein an ionic liquid catalyst is added for the reaction, wherein the ionic liquid catalyst comprises: 
       
         
           
           
               
               
           
         
         wherein R 1 , R 2 , and R 3  are independently H or a C 1 -C 6  alkyl group; 
       
       
         
           
           
               
               
           
         
         wherein R1, R2, R3, and R4 are independently H or a C1-C6 alkyl group; and 
       
       
         
           
           
               
               
           
         
         wherein R 1  and R 2  are independently H or a C 1 -C 6  alkyl group. 
       
     
     
       2. The method according to  claim 1 , wherein the ionic liquid catalyst comprises at least one anion selected from the group consisting of PF 6   − , BF 4   − , F 3 CSO 3   − , NO 3   − , I − , Br − , Cl − , CH 3 CO 2   − , and HCO 3   − . 
     
     
       3. The method according to  claim 1 , wherein the ionic liquid catalyst is used in an amount of 0.0025 moles or less per one mole of the glycerol carbonate. 
     
     
       4. The method according to  claim 1 , wherein a Lewis acid metal salt, together with the ionic liquid catalyst, is further added. 
     
     
       5. The method according to  claim 4 , wherein the Lewis acid metal salt is selected from the group consisting of Zn(NO 3 ) 2 , ZnCl 2 , SnCl 4 , MgCl 2 , AlCl 3 , and mixtures thereof. 
     
     
       6. The method according to  claim 4 , wherein the Lewis acid metal salt is added in an amount of 0.2 moles or less per one mole of the ionic liquid catalyst. 
     
     
       7. The method according to  claim 1 , wherein a solvent is further added in which the solvent is selected from the group consisting of polyethylene glycol dimethyl ether (DMPEG), dibenzyl ether, and dibutylphthalate. 
     
     
       8. The method according to  claim 1 , wherein the decarboxylation and glycidol collection are carried out simultaneously in a continuous process. 
     
     
       9. A method for producing glycidol comprising:
 putting together glycerol carbonate, 1-butyl-3-methylimidazolium nitrate, Zn(NO 3 ) 2 , and a solvent to form a mixture, wherein the solvent is selected from the group consisting of polyethylene glycol dimethyl ether (DMPEG), dibenzyl ether, and dibutylphthalate; 
 heating the mixture to not higher than 175° C. at ambient pressure; and 
 depressurizing the heated mixture to produce glycidol.